log5(x^2+4x)=log5(x^2+1)

Question

log5(x^2+4x)=log5(x^2+1)

Answer 1

ОДЗ: x^2+4x > 0

x(x+4) > 0

(-беск.; -4) U (0; +беск.)

x^2+1 > 0 --- х - любое

x^2+4x = x^2 + 1

4x = 1

x = 1/4

 

Answer 2

одз x^2+4x>0 =>  x>0 & x<-4 </span>

x^2+1 всегда >0

 

(x^2+4x)= (x^2+1)

4x=1

x=1/4